WASHINGTON (AP):

President George W. Bush dropped by the Republican party headquarters yesterday to implore workers to do their utmost for Republican presidential nominee John McCain.

But his political pep talk happened privately and out of the view of cameras and other media, a reflection of the president's record-low popularity and worries that outward support for McCain may drive away voters.

With the presidential campaign in its final week before the November 4 election day and the Republican nominee in an apparently uphill race to win, the president spent just over 20 minutes at the Republican National Committee's office in Washington.

Aides said he shook hands and spoke briefly to some 200 workers, including members of the Republican party's House and Senate campaign committees.

"He encouraged them to work hard for John McCain and keep turning out the vote until the final ballot is cast next week," said White House deputy press secretary Scott Stanzel. "He also took the opportunity to thank the staff for their efforts during this election cycle and for their support of him over the last eight years."

Presidential spokeswoman Dana Perino told reporters Bush felt it was important to encourage Republican Party operatives during the campaign's home stretch because it is usually "the most important week in a campaign."

McCain has said he knows he is running behind Democratic nominee Barack Obama, but pledges an upset victory. Polls are suggesting sizeable Democratic gains in Congress.

Throughout the campaign, the Republican has sought to distance himself from the unpopular sitting president. McCain and Bush have appeared together only once.